296 NOTES AND MEMOBANDA. 



and contain brown granules : the rectum is also lined witli a charac- 

 teristic epithelium. 



3. The circulatory system consists of a very narrow dorsal vessel, 

 the walls of which are composed of annular striated muscles; the 

 alary muscles appear to exist only in Scolopendra. 



4. The tracheje agree in their disposition and external appearance 

 with those of the larvse of insects (Lepidoptera), the stigmata are 

 provided with a simple but very characteristic valvular apparatus. '3 ^5 



5. Thebrainconsistsof fibres, and of cells of two kinds. The fibres 

 have a reticulated arrangement in the interior ; the cells of the first 

 kind are large, and uni-, bi-, or tripolar : those of the second kind 

 are much smaller, round or elliptical, and correspond to the cerebral 

 granules (Hirnkernen) of Dietl. The form of the brain is correlated 

 with the number of eyes and with the length of the body ; the longer 

 the body of the Chilopod, the fewer are its eyes, and the smaller its 

 optic lobes. The latter are wholly absent in the Himantaria. 



6. The structure of the eye resembles that of insect larvae. The 

 eyes of the Lithobii and Scolopendrce are quite like those of the larva 

 of Acilius, &c., or those of Sj^iders. The compound eye of Cermatia 

 consists of a number of lesser eyes, closely resembling those of the 

 larvfe of Hymenoptera. The optic lobes terminate in a small nerve, 

 the branches of which go to the separate eyes. 



7. The genital organs are very peculiar with regard both to their 

 external and internal structure. The ovary agrees closely in structure 

 with that of Araclinida. The eggs are disposed in grape-like bunches, 

 the ripe ones being covered with a layer of cells, probably epithelial. 

 The recepticula seminis exhibit epithelial and muscular layers. The 

 testis is filled with large quadrangular mother-cells with large nuclei, 

 probably derived from the epithelium of the thin upper part of the 

 gland. Its walls are invested with strong muscular bundles and a 

 layer of nuclei. The walls of the vesicula seminalis consist of an 

 epithelial layer and of a delicate network of muscles. 



8. Glands occur in great numbers in the mouth, in the thorax, on 

 the outer surface of the body, and on the appendages. The pores on 

 the coxfe (Coxalporen) are also glandular. The duct of the poison 

 gland is a strong chitinous canal with small tubules of the same 

 material opening into it ; each of these tubules terminates in a pear- 

 shaped gland-lobule. The whole gland-system is covered with a 

 characteristic layer of muscular fibres : so also is the nervous system. 



9. The organization of the short Chilopods with comparatively 

 few legs {Lithohius, Cermatia, Scolopendra) is higher than that of the 

 long Geophili and Himantaria. 



10. Of the other Arthropoda the Chilopoda are most nearly related 

 to the larvae of Lepidoptera, Hymenoptera, and Coleoptera. 



Polyxenus lagurus, De Gear. — Haller makes some remarks * on 

 this curious little Myriapod, which he got from under the bark of old 

 cherry-trees, though never in brushwood or hedges ; he draws attention 

 to the structures found in the caudal appendages of these animals, and 



* ' Arch, fiir Naturgeschichte,' xliv. (1878) 91. 



